Question

What is the equation of a circle with its center at (−6,−3) and a radius of 12?
(x+6)2+(y+3)2=12
(x+6)2+(y+3)2=24
(x+6)2+(y+3)2=144
(x−6)2+(y−3)2=12
(x−6)2+(y−3)2=144
could someone pls help me out with this
im very confused

Answer 1

If the centre is (a,b) and the radius is r , the equation would be
(x-a)^2 + (y-b)^2 = r^2

hint, since r = 12, r^2 would be 144, I see only two choices with that.
That sure limits it doesn't it?

Answer 2

recall that the equation of a circle with center at (h,k) and radius r is
(x-h)^2 + (y-k)^2 = r^2
so, you know that r^2 = 12^2 = 144
Now, which is your choice?

Answer 3

its (x+6)2+(y+3)2=144, just got it right.